Mica based glass - ceramics have been produced by subjecting the glasses in the SiO2 , Al2O3 , CaO , MgO, K2O , and F system to a controlled heat treatment called crystallization. TiO2 was added into the batch in the amount of 1 wt% of the glass as nucleating agent. B2O3 additions in the amounts of 1, 2, 4 and 8 wt% of the glass have been made in the batch to see and evaluate the effects of B2O3 additions on the texture of the mica glass ceramics. Crystallization was accomplished in two steps, nucleation and crystal growth. Nucleation temperature was 650 & / #61616 / C. Crystal growth temperatures were 850 and 1000 & / #61616 / C. The time for holding the specimens at the temperatures was 8 hours.
The X-Ray diffraction analysis revealed that resultant glass ceramics possessed not only synthetic fluormica crystals called phlogopite which provide machinability, but also wollastonite crystals which provide biocompatibility. The scanning electron microscopy examinations have indicated that the amount and distribution of the crystalline phases varied as a function of B2O3 content and heat treatment schedule applied.
| Identifer | oai:union.ndltd.org:METU/oai:etd.lib.metu.edu.tr:http://etd.lib.metu.edu.tr/upload/12606060/index.pdf |
| Date | 01 April 2005 |
| Creators | Aykut, Hakan |
| Contributors | Ozturk, Abdullah |
| Publisher | METU |
| Source Sets | Middle East Technical Univ. |
| Language | English |
| Detected Language | English |
| Type | M.S. Thesis |
| Format | text/pdf |
| Rights | To liberate the content for public access |
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